1, ATX power on →5V voltage to the south bridge ATX startup circuit → real-time clock work, to the CMOS circuit startup circuit to send 32.768KHz real-time clock signal.
2, press the power switch to send a power-on trigger signal to the NQ chip → trigger the power-on circuit to work, the 14th pin of the power interface becomes low → the ATX power supply starts to work.
3, each ATX pin supplies power to the motherboard and is powered on normally →ATX pin 8 sends 3V-5V PG signals to the CPU and BQNQ of the motherboard 4, the PG signal into NQ acts on the internal reset module, and the PG signal is connected to the RST# end of the system clock chip through NQ as a reset signal 5, reset signal RST# work →Clock clock chip also starts to work → Provide frequency signal to each hardware module of the motherboard → Each hardware module work 6, CPURST# is generated and sent to the foot, each hardware device is reset →CPU starts to work → the motherboard startup process is completed. 7, run the line: After finding the switch identification needle, from there is no grounding needle, to the direction of the south bridge to run, the power supply and ground line in the middle of the 4 layers of the board, and the signal to go up and down. Look at the back of the switch needle to see if there is a corresponding signal line, if there is, go along the direction of the signal line. Flow chart: